Would this work with an Android 3.0 Honeycomb Preview build, instead of a CM7 build ?

I have not tried. Depends if they have a similar rc.encore.init file that describes mounts.
Provide me with a link to an image and I'll tell you (and I can update the installer to work with it too).

Edit: I just checked with a file named HC-v4-emmc.zip from HC thread. Unfortunately it'll definitely won't work as it's not in an expected format. The zip file contains three tar files that need to be separately unpacked.
While it is possible to implement updating for this sort of an archive, it just looks like a one-tiem format that is not likely to be used by anything in the future.
Given that HC thread has SDCard installation instructions, I guess there is no point in supporting HC yet until things stabilize some more.

1. Follow verygreen's instructions in original post.
2. Then I setup my wireless.
3. Turned nook off and pulled sdcard.
4. Connected sd card to computer.
5. Make backup of uImage and uRamdisk
6. Renamed uRecImage to uImage and uRecRamdisk to uRamdisk
7. Downloaded the latest gapps zip file and copied it to the sd card.
8. Copied the update cm zip file that I originally used from the initial install back to the sd card.
9. Ejected card, inserted card into nook and booted up.
10. Recovery popped up and started to unzip both zip files.
11. Let it finish and then it will boot normally.
12. Once the nook boots, the initial sign pops up.
13. Skip everything until you get the normal home screen. None of the sign-in will work because it is looking for a phone signal.
14. Once you get to the home screen, make sure your wifi is still setup correctly and click on the market. Then follow the normal account setup directions.

Yea, there is a way... however when I tried it, things got very screwy (adw broke mainly). Something might have glitched, but I'll look into it again if the need arises. Based on other posts though, don't think I'll need to.

I don't know if I did it the right way, however I followed verygreen's steps as close as possible and I was easily able to install gapps as well. I'm on a Windows 7 machine, so maybe my steps were a bit different:

1) Burned the installer image to my uSD using Win32 Disk Imager
2) Downloaded CM nightly build (most current at the time was #26)
3) Copied this zip file directly to the burned image. (Like verygreen said there's only one partition)
4) Put the uSD card in my Nook and booted up.
5) Let verygreen's program work it's magic.
6) My Nook booted back up to my Stock Rooted, so I rebooted my Nook.
7) Booted right up to CM7!

Supposedly nothing. I routinely boot into eclair and then insert CM7 sdcard and it's fine.

I can't distribute gapps, like I said
Well, until I figure out why recovery boot does not work what you can try to do is this:
after initial install was successful (and you setup your wireless), power off the nook, get the sd card.
Download gapps-gb-...zip and put it on the first partition.
move the uImage file to uImage.bak and uRamdisk to uRamdisk.bak.
Copy uRecImage to uImage and uRecRam to uRamdisk.
boot with the resulting image. It should say that it found the gapps archive and unpack it.
After it flushes caches and reboots, power off, put the sd card back into the computer
move uImage.bak to uImage and uRamdisk.bak to uRamdisk
boot off the card again, hopefully the gapps are working after that.

Please let me know if any problems arise.

No problemo, thank you for all your care. A tidbit convoluted procedure, but quite understandable. Booting from shutdown takes >5 sec of pressing Power, otherwise it's just fine. Flash, YouTube, StreetView took manual installation from the Market, Flash 10.2/last YouTube give 2...5 fps, as was stated. Plus, when hiccuping and playing videos, the whole UI is becoming quite unresponsive. Well, takes some patience to wait for a streamlined ALSA. Though I still doubt it's purely ALSA/audio pipeline in video and its botched sync with video that makes video drop so many frames. Go out of sync then, but show smooth video, will ya? HWStagefright as fallback? VOME Engine from VisualOn?

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